Chemistry - January 2007

Is there any platinum at all in sterling silver?

2007-01-17 17:17:05 · 6 answers · asked by Anonymous

I know it's 22.4litres at stp and 24.47litres at 25 degs C, but what about 20 degs C?
Got any references to back up the figure?
Thanks!

2007-01-17 17:09:24 · 3 answers · asked by dkska; 2

When Epsom salt crystals MgSO4 are added to water it make water cold(er), Why?

2007-01-17 16:58:10 · 4 answers · asked by Anonymous

For example K, Fe, Cu, Na...atoms sizes compared to each other.

2007-01-17 16:51:08 · 4 answers · asked by Gideon 1

2007-01-17 16:48:19 · 4 answers · asked by r_rvaldez 2

I DONT UNDERSTAND THIS AT ALL! SO PLEASE EXPLAIN IT WELL SO I CAN UNDERSTAND IT? DO WE JUST GUESS AND CHECK AND CHOOSE A COEFFICIENT>? i dont get this!!!!!!!!!!!!!!!!!!

2007-01-17 16:35:26 · 2 answers · asked by Christina G. 3

A 7.25 kg sample of xenon is stored in a high-pressure cylinder with a volume of 10.0 L at 28.5 C. What is the pressure using the ideal gas equation and the pressure using van der Waals equation. Also, in regards to van der Waals equation, is the correction for volume or the correction for intermolecular forces more important in this case? Please help

2007-01-17 16:12:44 · 2 answers · asked by hibiscus2424 1

I did it, but it seemed too simple.

2007-01-17 16:08:09 · 2 answers · asked by hibiscus2424 1

A 5.00 L flask is filled with a sample of fluorine at a temp of 301.8 C. Calculate the average kinetic energy and rms speed in SI units.

2007-01-17 16:04:52 · 3 answers · asked by Anonymous

What are the Formulas for:

nichkel (III) sulfite
silver bromide
copper (II) bicarbonate
nickel (II) selenide
manganese (IV) carbonate
lead (IV) nitride
tin (II) hydroxide

2007-01-17 15:58:23 · 3 answers · asked by aaaaaaaaaaaaaa555 3

Suppose two analgesics have the same Rf value. How might you resolve their presence in a mixture using thin-layer chromatography?

2007-01-17 15:56:59 · 1 answers · asked by Anonymous

I know how to balance equations but its so hard for me!
i just keep getting all messed up
i want to ask 'how do you do it' but i know how to do it
only i cant really do it.
so basically can you teach me to balance in a way that makes sense?

2007-01-17 15:53:55 · 3 answers · asked by lo 2

The volume for 1 penny = .357ml
The volume for earth = 4/3(3.1416) (6375km)to the third=1.08x10to the 27thcmto the 3rd(cubic centimeters)

2007-01-17 15:53:14 · 1 answers · asked by FireFly 1

Im so lost. please help test tommorow

2007-01-17 15:52:26 · 2 answers · asked by keke 1

like special properties does it have that enables it to move? what about the reactions between the gasoline and air?

2007-01-17 15:42:44 · 9 answers · asked by Anonymous

Why does the Rf of 2,4-DTBP change dramatically compared with 2,6-DTBP with a change in solvent system?

2007-01-17 15:41:54 · 2 answers · asked by Anonymous

2007-01-17 15:39:03 · 3 answers · asked by Anonymous

having trouble about how the particles in substances
why would water have the lowest viscosity?
why would vegetable oil have a higher viscosity then water? even though its a lubricant
corn and maple syrup

2007-01-17 15:18:03 · 3 answers · asked by Matt 2

Ch3-C (double bond) CH-CH-C=CH-CH3
CH3

2007-01-17 15:16:03 · 3 answers · asked by Yoshi 2

protein isolation

2007-01-17 15:03:11 · 1 answers · asked by Anonymous

per mole of magnesium??

Mg+2HCL --> MgCl2 +H2

2007-01-17 14:58:06 · 4 answers · asked by Anonymous

2007-01-17 14:47:18 · 11 answers · asked by Anonymous

2007-01-17 14:45:33 · 4 answers · asked by Anonymous

What is a homoegeneous and hetrogeneous mixture?

2007-01-17 14:44:25 · 1 answers · asked by Anonymous

Thanks!

2007-01-17 14:40:39 · 3 answers · asked by yeahthatstheguy 1

Give the answer with the correct number of significant figures.

[(0.002843)(12.80184)]/ 0.00032=

2007-01-17 14:28:03 · 3 answers · asked by Alan l 1

Given the following densities at 25 C:
magnesium: 1.7 g/cm^3
graphite: 1.8 g/cm^3
iron: 7.9 g/cm^3

A block of iron has a mass of 826 g. What is the mass of a block of magnesium that has the same volume as the block of iron?

2007-01-17 14:24:45 · 1 answers · asked by Alan l 1

How do you figure out empirical formulas, and how would the answer be stated?

2007-01-17 14:23:56 · 4 answers · asked by !!! 3

Table salt ( sodium chloride) is 39.1% sodium. How many grams of salt contains 72.0 g of sodium?

2007-01-17 14:22:41 · 1 answers · asked by Alan l 1

water Fountains, lakes, effect on body

2007-01-17 14:18:14 · 4 answers · asked by Jocelyn 1